Flexible band fluid device

ABSTRACT

A fluid machine is provided which is operable as a pump, compressor, or fluid motor, or as a combined fluid motor and pump or compressor, and comprises a working member taking the form of a flexible band which divides a working chamber into inner and outer working chambers and is flexurally movable through a cycle of operation therewithin to alternately expand and contract respective portions of said inner and outer working chambers. Inlet and outlet passages are provided in fluid flow communication with each of said inner and outer working chambers and are operable to enable the pumping or compression of fluid therethrough when the fluid machine is utilized as a pump or compressor, and/or to admit fluid under pressure thereto and exhaust the same therefrom when the fluid machine is utilized as a fluid motor or a combined fluid motor and pump or compressor.

United States Patent 72] Inventor Friedrich 0. Bellmer Stanhope, NJ.

[21] App1.'No. 783,686

[22] Filed Dec. 13, 1968 [45] Patented Dec. 14, 1971 [73] Assignee Worthington Corporation Harrison, NJ.

[54] FLEXIBLE BAND FLUID DEVICE 45 Claims, 67 Drawing Figs.

[52] U.S. Cl 418/45 [51] Int.Cl F044: 5/00 [50] Field 01 Search 103/148, 149,117,117 R; 230/137, 160, 168; 91/57;92/48, 89, 94,95, 105

[56] References Cited UNITED STATES PATENTS 2,336,580 12/1943 Yeatman 103/117 R 2,581,830 1/1952 Averill 91/57 2,585,949 2/1952 MacCormack. 103/149 2,691,365 10/1954 Lehmann, Jr... 91/57 2784902 3/1957 Glenn 7 3,050,013 8/1962 Ketterer 103/149 FOREIGN PATENTS 1,343,699 10/1963 France 103/1 17 R Primary Examiner-Mark Newman Assistan! Examiner- Wilbur .l Goodlin Attorney-Daniel H. Bobis ABSTRACT: A fluid machine is provided which is operable as a pump. compressor, or fluid motor, or as a combined fluid motor and pump or compressor, and comprises a working member taking the form of a flexible band which divides a working chamber into inner and outer working chambers and is flexurally movable through a cycle of operation therewithin to alternately expand and contract respective portions of said inner and outer working chambers. Inlet and outlet passages are provided in fluid flow communication with each of said inner and outer working chambers and are operable to enable the pumping or compression of fluid therethrough when the fluid machine is utilized as a pump or compressor, and/or to admit fluid under pressure thereto and exhaust the same therefrom when the fluid machine is utilized as a fluid motor or a combined fluid motor and pump or compressor.

PATENTEnbEmMsn 1621.452 saw our 10,

M A 70 FRIEDRICH O. BELLMER INVENTOR.

22 5 30 4o 8 l0 BY FIG. 7

PATENTED DEC! 4 BR SHEEI 02 I 10 FIIGJJIA FIG.IIB FIG.I'IC mum FIGQIZ FIG.|4

FRIEDRICH O.BELLMER BY $MALM PATENTEU DEC I 4 12m SHEET [BM 10 FRIEDRICH O. BELLMER INVENTOR.

$MMM PATENTEDDECMIHTI 3,627,452

SHEET ONE 10 FRIEDRICH O. BELLMER INVENTOR.

PATENTEDUEBMIHII 3,627,452

SHEET 05 0F 10 FRIEDRICH o. BELLMER INVENTOR.

BY %@u/-1 M PATENTED UECMIHYI 3,627,452 sum near 10 FIG.46 FIG.47

FRIEDRICH O. BELLMER INVENTOR.

BY$MMM PATENTED 05cm Ian 3,627,452 sum 07 or 10 FRIEDRICH O. BELLFg ER INVENT 4IZ 4oa BY N. 4 r

PATENTEUUEBMIQTI 3.6273152 SHEET 080! 10 I02 8a lo 5 FIG.57

FRIEDRICH O. BELLMER BY 'N- PATENTEUnEcMmn 3.6273152 swan OSUF 10 FRIEDRICH O. BELLMER IN VENTOR.

BACKGROUND OF THE INVENTION This invention relates to a new and improved fluid machine which is adaptable for use as a pump, a compressor or a fluid motor, or as a combined fluid motor and pump or compressor.

Although fluid machines of these general classifications are, of course, very well known, it is believed equally well known that there is substantial room for improvement, in a wide variety of areas, with regard to the current, or state of the art, embodiments thereof. More specifically it may be readily understood by those skilled in this art that although currently available fluid machines of these classifications do offer satisfactory performance, there is, nonetheless, substantial room for improvement thereof in such highly significant and, to some extent, interrelative areas as unduly high initial and operational cost, undue machine complexity both in design and number of working components, unduly high-power consumption resulting from high frictional losses, unduly high mass of the moving or working members, unduly high sliding speeds of the working members with attendant high frictional losses and machine component wear rates and requirements for relatively expensive machine component materials of suitable strength and hardness characteristics, lack of machine reliability and difficulty in replacing worn or damaged components, unduly high noise levels, unduly high space requirements and operational weights, with regard to the displacement provided thereby, lack of ready and convenient convertability from the performance of one function to the performance of another function without major modification as, for example, from pump to compressor or from fluid motor to fluid motor driven pump, lack of ready and convenient reversability of operation, and a general inability for the simultaneous performance of two distinct fluid working functions.

OBJECTS OF THE INVENTION It is, accordingly, an object of this invention to provide a fluid machine which is of extremely simple construction with resultant relatively low cost.

Another object of this invention is the provision of a fluid machine which embodies an extremely low speed of the working member despite high drive shaft speeds to thus minimize frictional losses with attendant minimization of machine component wear rates.

Another object of this invention is the provision of a fluid machine which is of extremely durable design and construction and extremely simple manner of operation, whereby long periods of satisfactory, maintenance-free operation thereof are assured.

Another object of this invention is the provision of a fluid machine which requires but a single major working component of very low relative mass readily and conveniently replaced at low cost.

Another object of this invention is the provision of a fluid machine of significantly reduced power consumption requirements resulting from the reduced operational friction therefor.

Another object of this invention is the provision of a fluid machine which embodies a very low operational noise level.

Another object of this invention is the provision of a fluid machine which is of very low relative weight and requires relatively little space.

Another object of this invention is the provision of a fluid machine which, without major internal modification, is readily convertible between such applications as a pump, a compressor, a fluid motor, and a fluid motor driven pump or compressor.

A further object of this invention is the provision of a fluid machine which is readily and conveniently reversible in operation without any internal modifications and without loss in efficiency BRIEF DESCRIPTION OF THE INVENTION As currently preferred, the fluid machine of the invention comprises a housing having an aperture formed therein and a core disposed within said aperture and spaced therefrom to form a working chamber, therebetween. A single working member which takes the form of a flexible band is disposed within said aperture to surround said core at least in part and divide said working chamber into inner and outer working chambers, respectively. Fluid passages are provided to extend through said housing and core, respectively, into fluid flow communication with said outer and inner working chambers and are operative as inlet and outlet passages to result in the formation of outer and inner working sections of the fluid machine. For use as a pump or compressor, external power is applied to the flexible band to flexurally move the same through a cycle of operation which alternately covers and uncovers said outlet and inlet passages and concomitantly expands and contracts respective portions of said outer and inner working chambers to result in the pressurization and movement of fluid between said inlet and outlet passages of said inner and outer working sections respectively. For use as a fluid motor, fluid under pressure is introduced through said inlet passages of the respective inner and outer working sections to flexurally move said flexible band through its cycle of operation and enable the application thereby of rotational power or torque to power takeoff means in the nature of shaft means. For use as a combined fluid motor and pump or compressor, pressurized fluid is admitted to one working seetionto flexurally move the flexible band through its cycle of operation and pump or compress fluid through the other of said working sections. For use as a fluid meter, it may be understood that the passage of a measured quantity of fluid through the fluid machine of the invention will be effective to move the flexible band through one cycle of operation to provide accurate indication of such fluid passage. In all applications, the fluid machine of the invention is inherently and conveniently reversible in operation.

DETAILED DESCRIPTION OF THE DRAWINGS The above and other objects and advantages of the fluid machine of this invention are believed made clear by the following detailed description thereof taken in conjunction with the accompanying drawings wherein:

FIG. 1 is a side elevational view of a fluid machine constructed in accordance with my invention;

FIG. 2 is atop elevational view of the fluid machine of FIG. 1;

FIG. 3 is an end view of the fluid machine of FIG. 1;

FIG. 4 is an opposite end view of the fluid machine of FIG.

FIG. 5 is an exploded perspective view of the fluid machine of FIG. 1;

FIG. 6 is an end view of the fluid machine of FIG. I with the cover plate removed;

FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 6;

FIG. 8 is an end view of one fonn of flexible band attachment means;

FIG. 9 is an end view of another fonn of band attachment means;

FIG. 10 is an end view of another form of band attachment means;

FIG. 11A through 1 ID illustrate a cycle of operation for the fluid machine of FIG. 6;

FIG. 12 is an end view, with the cover plate removed, of a form of the fluid machine of the invention which is particularly adaptable for use as a compressor;

FIG. 13 is a cross-sectional view of another form of the fluid machine of the invention:

FIG. 14 is a cross-sectional view taken on line 14-14 in FIG. 13;

FIG. 15 is a cross-sectional view of another form of the fluid machine of the invention;

FIGS. 16 through 19 are end views of another form of the fluid machine of the invention with the cover plate removed, and illustrates a cycle of operation thereof;

FIG. 20 is a cross-sectional view taken through a form of the fluid machine of the invention which includes means effective to vary the displacement ratio between the outer and inner working chambers;

FIGS. 21 through 23 are schematic illustrations of the working parts of the fluid machine of FIG. 20 set at different working chambers displacement ratios;

FIG. 24 is a cross-sectional view taken through a fluid machine portion incorporating another form of flexible banddrive pin attachment means;

FIG. 25 is a cross-sectional FIG. 24;

FIG. 26 illustrates still another form 'of flexible band-drive pin attachment means;

FIG. 27 is an end view, with the cover plate removed, of another form of the fluid machine of the invention.

FIG. 28 is an edge view of the flexible band utilized in the fluid machine of FIG. 27;

FIG. 29 is a cross-sectional view taken through a form of the fluid machine of the invention which means permitting the adjustment of the effective length of the flexible band-driving fluid machine operation;

FIG. 30 is an end view, with the cover plate removed, of another form of the fluid machine of the invention;

FIG. 31 is an edge view of the unstressed flexible band members utilized in the construction of the flexible band of the fluid machine of FIG. 30;

FIG. 32 is an edge view of the band members of FIG. 31 in the prestressed condition thereof;

FIG. 33 is an end view, with the cover plate removed, of a fluid machine incorporating another form of flexible banddrive pin attachment;

FIG. 34 is an enlarged view of the flexible band-attachment pin connection of the fluid machine of FIG. 33;

FIG. 35 is an enlarged, cross-sectional view of the flexible band-drive pin connection of the fluid machine of FIG. 33;

FIG. 36 is a perspective view of the flexible band-drive pin connection of FIG. 35;

FIG. 37 is a cross-sectional view of another form of the fluid machine of the invention and illustrates the utilization therein of the flexible band-attachment pin and drive pin connections of FIGS. 34 and 35;

FIG. 38 is a cross-sectional view of another form of the fluid machine of the invention and illustrates the utilization therein of the flexible band-attachment pin and drive pin connections ofFIG. 34 and 35;

FIG. 39 is an edge view of a flexible band of laminated construction and generally circular shape;

FIG. 40 is an edge view of a flexible band of laminated construction and generally heart-shaped;

FIG. 41 is a cross-sectional view taken on line 41-41 in each of FIGS. 39 and 40;

FIG. 42 is a cross-sectional view of another form of flexible band-drive pin connection for a flexible band of laminated construction;

FIG. 43 illustrates a laminated band of initially generally circular configuration at different points in a cycle of flexible operation thereof;

FIG. 44 is an edge view of a multipart flexible band incorporating band edge sealing means therein;

FIG. 45 is a layout plan view of a component part of the flexible band of FIG. 44;

FIG. 46 is an enlarged plan view of a different component part of the flexible band of FIG. 44;

FIG. 47 is an enlarged plan view of still a different component part of the flexible band of FIG. 44;

FIG. 48 is a cross-sectional view taken through a portion of a fluid machine incorporating the flexible band of FIG. 44;

FIG. 49 is a cross-sectional view taken through a portion of a fluid machine incorporating a somewhatdifferent' form of multipart flexible band;

view taken on line 25-25 in FIG. 50 is a side elevational view illustrating a form of the fluid machine of the invention which includes flexible band cooling means;

FIG. 51 is a cross-sectional view taken on line 51-51 in FIG. 50;

FIG. 52 is a cross-sectional view taken on line 52-52 in FIG. 51;

FIG. 53 is a cross-sectional view taken on line 53-53 in FIG. 51;

FIG. 54 is a cross-sectional view taken through another form of the fluid machine of the invention which incorporates flexible band cooling means therein;

FIG. 55 is an end view. with the cover plate removed, of a multiunit form of the fluid machine of the invention;

FIG. 56 is a cross-sectional view taken on lines 56-56 in FIG. 55.

FIG. 57 is an end view, with the cover plate removed, of another multiunit form of the fluid machine of the invention;

FIG. 58 is an end view, with parts broken away and a portion in cross section, illustrating another multiunit form of the fluid machine of the invention;

FIG. 59 is a side elevational view, with a portion in cross section, of the fluid machine of FIG. 58;

FIG. 60 is an exploded perspective view of the flexible band-drive pin connection assembly of the fluid machine of FIGS. 58 and 59;

FIG. 61 is an end view, with parts broken away and portions in cross section; of still another multiunit form of the fluid machine of the invention;

FIG. 62 is a cross-sectional view taken through a form of the fluid machine of the invention incorporation common inlet and outlet means;

FIG. 63 is a cross-sectional view taken through a form of the fluid machine of the invention incorporating common inlet and outlet means and a substantially thicker flexible band; and

FIG. 64 is a cross-sectional view taken on line 64-64 in FIG. 63.

DETAILED DESCRIPTION OF THE INVENTION Referring now to FIG. 1 through 4 of the drawings, a fluid machine constructed in accordance with the teachings of the invention is indicated generally at 2 and may be seen to comprise a generally cylindrical casing 4 which includes, in the manner best seen in FIG. 1 and 2, a front plate 6, a housing 8 and a backplate l0 maintained in the depicted side-by-side relationship thereof by attachment bolt means as indicated at 12 extending therethrough. As best seen in FIG. I, a drive shaft 14 extends from the backplate 10 through a drive shaft bushing 16 (FIG. 4) provided therefor into operativeconnection with any convenient source of rotational power as, for example, an electric drive motor as indicated at 18. Alternatively, were the fluid machine 2 to be utilized as a fluid motor, element 18 could, for example, be operated as transducer means in the nature of an electric generator.

Spaced fluid conduits 20, 22, 24 and 26 are provided to extend as shown from the front plate 6 and, assuming driven rotation of the drive shaft 14 in the clockwise direction as seen in FIG. 4, it may be understood that fluid conduits 20 and 24 will function as inlet conduits while fluid conduits 22 and 26 will function as discharge conduits. Conversely, assuming driven rotation of the drive shaft 14 in the counterclockwise direction as seen in FIG. 4, fluid conduits 22 and 26 will function as inlet conduits while the fluid conduits 20 and 24 will function as discharge conduits, it thus being made clear that the fluid machine of the invention is readily reversible in operation for reasons described in greater detail hereinbelow.

Referring now to the exploded perspective view of FIG. 5, it may be seen that the front plate 6 comprises spaced, generally parallel fluid passages extending completely therethrough and formed in substantial alignment and fluid flow communication with the respective fluid conduits 20, 22, 24 and 26. More specifically, and as indicated-in dashed lines in the subject Figure, a fluid passage 28 is formed to extend completely through the front plate 6 in substantial alignment with the fluid conduit 22; a fluid passage 32 is formed to extend completely through the said front plate in substantial alignment with the fluid conduit 24; and a fluid passage 34 is similarly formed with regard to the fluid conduit 26.

The housing 8 is of the depicted, generally toruslike configuration including a relatively large, generally centrally disposed aperture 36 formed to extend therethrough. Further included in the housing 8 are fluid passages or slots as indicated at 38 and 40, respectively, and generally semicircular cutouts as indicated at 42 and 44, respectively, with each of the said slots and cutouts being formed to extend as shown into fluid flow communication with the aperture 36 in the housing 8 for purposes described in greater detail hereinbelow.

Further included in the fluid machine of FIG. 5 is a generally cylindrical core 46 which, in the manner of the housing 8, includes spaced, fluid passages or slots 47 and 48, respectively, formed as shown to extend inwardly from the periphery thereof, a generally semicircular cutout 50 similarly formed in the periphery thereof intermediate the said slots, and a cutout 51 formed as shown in the upper peripheral portion thereof. As depicted, the core 46 comprises apertures 52 and 54 formed to extend therethrough in substantial alignment with threaded apertures 56 and 58 which are provided in the adjacent end face of the backplate l0, and attachment bolts as indicated at 60 and 62 are provided for use in attaching the said core to the said backplate in obvious manner as nonetheless described in greater detail hereinbelow.

A drive shaft bushing mounting aperture 64 is formed as shown to extend through the backplate and it may be understood that the drive shaft bushing 16 is disposed in the said backplate by the simple insertion or press fitting of the said bushing in the said mounting aperture. A drive pin mounting aperture 66 is eccentrically disposed as shown in the extremity or end face of the drive shaft 14, and a drive pin 68 is provided for disposition with freedom for rotation, in the said drive pin mounting aperture.

A flexible band 70 is provided and is preferably, although no necessarily, formed or prestressed into the depicted generally toruslike configuration thereof prior to band utilization. As seen in FIG. 5, the flexible band 70 comprises attachment apertures 72 and 74 formed adjacent the respective extremities thereof, and attachment means in the nature of a rivet 76 are provided to attach the respective band extremities in a manner described in greater detail hereinbelow.

The respective thicknesses of the core 46 and housing 8 are made substantially equal, and the width of the flexible band 70 is made very slightly less than this housing and core thickness for reasons made clear hereinbelow. A band attachment slot 78 is formed as shown in one extremity of the drive pin 68 and it may be understood that operative connection of the flexible band 70 to the said drive pin may readily be efiected by the insertion of the former into the said band mounting slot. Thereafter, a rivet 79 is passed as indicated through aligned apertures provided therefor in the drive pin 68 and flexible band 70.

In assembling the respective parts of FIG, 5 to form the fluid machine of the invention in accordance with a currently preferred, although by no means exclusive, method of fluid machine assembly, it may be understood that the core 46 would be securely attached to the back plate 10 by the placement of the former into firm surface contact with the adjacent and face of the latter and the subsequent tightening of the attachment bolts 60 and 62 through the apertures 52 and 54 of the core 46 into the threaded apertures 56 and 58 of the backplate l0. Alternately, it is believed clear that the core 46 and backplate 10 could, of course, be formed integrally to thus obviate the necessity for this attachment step.

Following this core-backplate attachment step, or the integral formation thereof as the case may be, the drive shaft 14 is extended through the drive shaft bushing 16 to an extent that will place an end face of -the former flush with the end face of the backplate l0, whereupon the drive pin 68 is inserted with freedom for rotation into the drive pin mounting aperture 66 which, as discussed hereinabove, is eccentrically disposed in the said drive shaft end face. Following this, the respective extremities of the flexible band 70 are joined by the passage of the rivet 76 through the band attachment apertures 72 and 74 and the closure of the said rivet whereupon the thusly connected band is inserted over the core 46 with the upper portion of the said band being inserted into the band mounting slot 78 in the drive pin 68 within the core cutout 51, and the riveted extremities of the said band being inserted into the generally semicircular cutout 50 formed in the core 46.

Following this, the housing 8 is inserted over the thusly assembled core, drive pin and flexible band in such manner that the generally semicircular housing cutout 42 overlays the drive pin 68, and the generally semicircular housing cutout 44 overlays the riveted band extremity connection. It thus may be understood, in the manner made clear by FIG. 8, whereby a generally circular mounting aperture will be formed for the riveted band extremities by the complemental disposition of the respective core cutout 50 and the housing cutout 44 to thus maintain the said riveted band extremities substantially stationary as described in greater detail hereinbelow. In like manner, it may be understood that a generally circular aperture will be formed by the complemental disposition of the respective housing cutout 42 and core cutout 51 for movement of the drive pin 68 therewithin in a generally circular path as described in greater detail hereinbelow.

Subsequently, the front plate 6 is placed in surface contact with the respective adjacent end faces of the core 46 and the housing 8, and the attachment bolt means 12 tightened through the aligned apertures 13 provided therefor in the respective front plate 6, housing 8 and back plate 10 to assemble these components in the side-by-side relationship thereof depicted in FIGS. 1 and 2, it being understood that such tightening of the attachment bolt means 12 will be sufficient to ensure a fluidtight seal between the respective contacting end faces of the said front and backplates and housing. In addition, by such assembly it may be understood that the respective fluid passages 28 and 30 in the front plate 6 will be brought into alignment with the radially outer portions of the respective slots 38 and 40 of the housing 8 to thus provide for fluid flow communication therebetween while, in like manner, the respective fluid passages 32 and 34 of the front plate 6 will similarly be brought into substantial alignment with the radially inner portions of the slots 47 and 48 of the core 46 to ensure fluid flow communication therebetween.

With the respective components thusly assembled to form the fluid machine as depicted in cross section in FIG. 7, and in end elevation in FIG. 6 with the front plate 6 removed, it may be seen that a chamber as indicated generally at 80 in FIGS. 6 and 7 will be formed between the periphery of the core 46 and the face of the aperture 36 of the housing 8. Further, it may be understood that this chamber 80 will be divided by the flexible band 70 into an inner fluid working chamber 82 and an outer fluid working chamber 84, with fluid communication therebetween being substantially inhibited by the sealing effects of the respective edges of the flexible band against the respective inner'end faces of the front plate 6 and backplate 10 as described in greater detail hereinbelow.

With the respective fluid machine components assembled as illustrated by FIGS. 6 and 7, it may be understood that a first fluid flow path or fluid machine working section will be established to extend through fluid conduit 20 and fluid passage 28 in front plate 6, fluid passage or slot 38 in housing 8, the outer fluid working chamber 84 formed between the outer surface of the flexible band 70 and the face of the aperture 36 in the housing 8, the fluid passage or slot 40 in the housing 8, the fluid passage 30 in the front plate 6 and the fluid conduit 22 which extends therefrom, In like manner, a second fluid flow path or fluid machine working section will be formed to extend through fluid conduit 24 and through passage 32 in the front plate 6, fluid passage or slot 47 in the core 46, the inner working chamber 82 formed between the inner surface of the flexible band 70 and the outer periphery of the core 46, fluid passage or slot 48 formed in the core 46, the fluid passage 34 formed in the front plate 6 and the fluid conduit 26 extended therefrom.

As clearly illustrated in FIG. 6, it may be understood that the respective riveted extremities of the flexible band 70 will be maintained substantially stationary within the mounting aperture provided therefor by the complemental disposition of the respective cutouts 44 and 50 of the housing 8 and core 46. Accordingly, the drive rotation of the drive shaft 14 in the counterclockwise direction as seen in FIG. 6, with attendant description by the eccentrically disposed drive pin 68 of a circular path about the center of the said drive shaft, within the aperture provided therefor by the complementally disposed core and housing cutout 51 and 42, will result in the said drive pin carrying with it the upper portion of the flexible band 70 in such manner that every point on the flexible band 70 which is farther away from the said drive pin will be flexurally moved on a shorter path until, or course, the point at which the respective band extremities are attached by the rivet 76 is reached, at which latter point the band movement will be substantially zero.

This flexural I movement of the flexible band 70 which results from the driven rotation of the drive shaft 14, and the manner in which fluid may be moved as a result thereof, are believed made clear by FIGS. 11A through 11D, which illustrate flexible band position and fluid device operation for one complete rotation of the drive shaft 14. Thus, assuming the rotation of the drive shaft 16 to be in the counterclockwise direction as indicated by the arrows in these Figures, and the fluid device to be employed as a liquid pump to pump liquid from an inlet conduit 20 to an outlet conduit 22 and to simultaneously pump liquid from an inlet conduit 24 to an outlet conduit 26 all as seen in FIGS. 3 and 5, it may be noted that with the drive pin 68 in the bottom dead center position thereof as illustrated in FIG. 11A, the flexible band 70 will be so disposed as to prevent fluid flow between either of the fluid passages or slots 38 and 40 and the outer fluid working chamber 84. At this point, however, each of the fluid passages or slots 47 and 48 will be uncovered by the flexible band 70 and will thus be in fluid flow communication with the inner fluid working chamber 82. Accordingly, as the drive shaft 14 rotates 90 in the counterclockwise direction from the position thereof depicted in FIG. 11A to the position thereof depicted in FIG. 118, the left-hand portion of the inner fluid working chamber 82 will be substantially decreased in volume by the flexural movement of the flexible band 70 from contact with the face of the aperture 36 to contact with the periphery of the core 46 whereby may be understood that the liquid present in this inner working chamber portion will be forced therefrom through fluid passage or slot 48 in core 46 and therefrom through passage 34 in front plate 6 for discharge through discharge conduit 26. This liquid flow will, of course, continue, until closure of the slot 48 by the flexible band 70 as seen in FIG. 1 1B.

Concomitantly, the right-hand portion of the inner working chamber 82 will commence to increase in volume whereupon liquid will be drawn thereinto through inlet conduit 24, fluid passage 32, and slot 47. In addition, this flexural movement of .the flexible band 70 will function to substantially decrease the volume of the right-hand portion of the outer working chamber 84 to displace the fluid therefrom to the left-hand portion of the said outer working chamber, while concomitantly uncovering fluid passage or slot 40, whereby the discharge of liquid from the left-hand portion of outer working chamber 84 through slot 40, connected passage 30 and fluid conduit 22 will commence. This liquid discharge through slot 40 will continue as the drive pin 68 moves another 90 to the position depicted in FIG. 11C whereupon the flexible band will have covered both fluid passages or slots 47 and 48 to temporarily prevent further fluid flow therethrough while uncovering fluid passage or slot 38 and effecting a substantial increase in volume in the right-hand portion of outer working chamber 84 with resultant liquid flow thereinto through inlet conduit 20, fluid passage 28, and the said slot 38.

Rotational movement of the'drive pin 68 from the position thereof depicted in FIG. 11C to the position thereof depicted in FIG. 11D will result in the substantially complete discharge of all liquid in the left-hand portion of outer working chamber 84 therefrom through the slot 40 for discharge through fluid passage 30 and discharge conduit 22 with subsequent closure of the slot 40 by the flexible band 70 to prevent further fluid flow therefrom. Concomitantly, this flexural movement of the flexible band 70 will function to displace the liquid contained in the upper portion of the inner working chamber 82 as seen in FIG. 11C to the left-hand portion of the said inner working chamber as seen in FIG. 11D, while at the same time reopening fluid flow communication between the said inner working chamber portion and slot 48 whereby the discharge of liquid through the latter and through connected fluid passage 34 and outlet conduit 26 will occur. In addition, it may be understood that this flexural movement of the flexible band 70 from the position thereof depicted in FIG. 11C to the position thereof depicted in FIG. 11D will result in substantial increase in volume in the right-hand portion of the outer working chamber 84 to draw additional liquid thereinto through slot 38, for subsequent displacement therefrom and discharge from the left-hand portion of the outer working chamber 84 upon the movement of the drive pin 68 and flexible band 70 from the respective positions thereof depicted in FIG. 1 1D to the respective positions thereof depicted in FIG. 118.

With the return of the 'flexible band 70 from the position thereof depicted in FIG. [ID to the position thereof depicted in FIG. 11A, one cycle of fluid machine operation will be completed with the closure of the slots 40 and 38, the continuance of the discharge of liquid from the left-hand portion of the inner working chamber 82 through the slot 48, and the uncovering of the slot 47 by the flexible band 70 with attendant increase in the volume of the right-hand portion of the inner working chamber 82 to effect the drawing of fluid thereinto through the slot 47.

Thus it is believed made clear that the fluid machine of the invention, when operated as a liquid pump with rotational power supplied thereto through drive shaft 14, will be double acting in comprising two simultaneously operative working sections, namely, an outer working section which includes slot 38, the outer working chamber 84 and slot 40', respectively, and an inner working section which includes slot 47, the inner working chamber 82 and the slot 48, respectively.

Alternatively, it is believed clear that through suitable introduction of a fluid under higher pressure than that to be pumped to one of these working sections, preferably the inner working section through slot 47 to prevent inwardly directed collapse of the flexible band 70 due to the resultant force developed by the pressure differential, the fluid machine of FIG. 6 would be eminently suitable for use as a motor driven pump complete in itself. More specifically, it may be understood that under such operational conditions, no rotational power need be applied to the drive shaft 14 and that the introduction of this higher pressure fluid to the inner working chamber, through slot 47 for example, would cause the inner working section to act as a fluid motor and flexurally move the flexible band 70 through repeated cycles of operation thereof as depicted in FIGS. 11A through 11D to effect the pumping of a liquid by the outer working section in the same manner as described in detail hereinabove as resulting from the driven rotation of the drive shaft 14. Alternatively, a motor driven compressor may be fonned with the utilization, under these conditions, of the outer working section as a compressor.

As another alternative, it is believed clear that the introduction of a fluid under pressure in turn to each of the slots 38 and 47 will result in the formation of a single stage, double-acting fluid motor to provide rotational power to the drive shaft 14 which, under such conditions, would be drivingly rotated in the counterclockwise direction as seen in FIG. 6 by the flexural movement of the flexible band 70 through repeated cycles of operation thereof as illustrated by FIGS. 11A through 11D.

Whether utilized as a fluid pump, compressor, or fluid motor, it is believed clear that staging may readily be effected in the fluid machine of the invention as depicted in FIG. 6. Thus, if the machine is to be utilized as an externally driven fluid pump, suitable connection of outlet conduit 22 to inlet conduit 24 as seen in FIG. will, of course, result in the formation a single-acting, two stage pump with the higher pressure again being maintained in the inner working chamber 82. In like manner, and for use as a fluid motor, suitable connection of outlet conduit 26 to inlet conduit 20 will result in the formation of a single-acting, two stage fluid motor with the higher pressure again being maintained in the inner working chamber 82.

In all forms of the fluid machine of the invention as discussed hereinabove, that is to say whether the same is utilized as an externally driven fluid pump or compressor, an intemally driven fluid motor pump or compressor combination, or a fluid motor, it is to be clearly understood that the fluid machine of the invention is completely and readily reversible in operation. Thus, for use as an externally driven fluid pump, driven rotation of drive shaft 14 in the clockwise direction as seen in FIG. 6 will cause fluid conduits 24 and 20 to function as discharge conduits. In like manner, and for use as a fluid motor, the introduction of the driving fluid through conduits 22 and 26 (FIG. 5) will effect driven rotation of the drive shaft 16 in the clockwise direction as seen in FIG. 6.

A problem that can arise through operation of the fluid machine of the invention as a compressor resides in the fact that the particular housing and core slots which are functioning as discharge valves in fluid flow communication with the discharge conduits may be opened by the flexural movement of the flexible band 70 to uncover the same before the fluid being compressed in the relevant working chamber has assumed a sufficient pressure to enable the flow thereof from the said working chamber to a storage device in the nature of the compressed fluid receiver. More specifically, as depicted in FIG. 12 wherein the flexible band 70 may be seen to be in substantially the same position as illustrated in FIG. 118, it may be understood that compressed fluid from the outer working chamber 84 is to flow, through discharge conduit 22, to a compressed fluid receiver as indicated at R. Accordingly, as the flexible band 70 is flexurally moved from the bottom dead center position thereof as depicted in FIG. 11A, to the position thereof depicted in FIG. 12 to uncover housing slot 40, it may be that the fluid in the outer working chamber 84 has not yet been sufficiently compressed to assume at least the pressure of the compressed fluid stored in the receiver R whereby a most obviously ineflicient backflow of compressed fluid from the receiver R through discharge conduit 22 and into the outer working chamber 84 will take place.

A simple and most effective means of preventing this undesirable receiver working chamber backflow is depicted in FIG. 12 and may be seen to constitute the interposition of a check valve CV in the discharge conduit 22 between the receiver R and the outer working chamber 84 to render sub stantially impossible the occurrence of such backflow from the receiver R and thus ensure maximum efficiency for the fluid compression operation.

Alternatively, it may be understood that such backflow from the receiver R may be substantially prevented through suitable design of the respective configuration of the housing aperture 36 and the core 46, and suitable determination of the effective length of the flexible band 70, to ensure that the relevant core and/or housing slots which are functioning as the discharge valve or valves will not be uncovered and opened by the flexural movement of the flexible band 70 until such time as the fluid being compressed in the relevant working chamber or chambers has assumed a pressure sufficient to prevent such backflow.

Alternate method of flexible band extremity attachment as further examples are depicted in FIGS. 9 and 10, respectively. Thus, as seen in FIG. 9, the respective band extremities are bent into generally semicircular form as indicated at and 92, respectively, and inserted into the respective complementally shaped cutouts 50 and 44 of the core 46 and housing 8, whereupon a pin 94 is inserted between the said ring extremities to firmly affix the latter within the thusly formed ring mounting aperture. A particular advantage of the ring extremity attachment means depicted in FIG. 9 resides in the fact that the same provide for some freedom of rotation of the respective ring extremities about the attachment pin 94 and may thus be understood to inhibit somewhat the stressing of the said ring extremities.

As seen in FIG. 10, the respective ring extremities are simply bent to an approximately 90 extent and a complementally shaped slot as indicated at 96 provided therefor in the core 46 whereupon it may be understood that suitable insertion of the thusly bent ringextremities into the said slot will function to satisfactorily position and the said ring extremities relative the core 46. A particular advantage of this method of flexible band extremity attachment resides, of course, in the distinct simplicity thereof as should be obvious.

Referring now to the form of FIGS. 13 and 14 it may be seen that the housing utilized therein is of substantially different shape than the housing 8 of the form of FIG. 5, more specifically the housing 150 includes an aperture 152 formed therein which extends completely through a peripheral portion thereof. In like manner, the core 156 is of substantially different shape, although again being complementally shaped with regard to the aperture 152 of the housing 150. In this form, the flexible bland 70 is maintained discontinuous and, although again drivingly connected to the drive pin 68 through insertion in a drive pin slot 78, is affixed directly to the core 156 at spaced points in the latter. To this latter effect, at tachment pins 158 and 160 are provided to extend through apertures 162 and 164 provided therefor in the core I56, and the attachment of the respective band extremities to the said attachment pins is effected by the simple expedient of bending the said extremities around the said pins and inserting the respective band attachment pin combinations into the respective core apertures 162 and 164. Alternatively, it is believed clear that any other of the disclosed methods of flexible bandpin attachment means may be utilized here. Fluid passages or slots I66 and 168, respectively, are provided to extend into communication with the respective rightand left-hand portions of the outer working chamber 84 by spaces between the respective housing walls and 172 and the respective core walls 174 and 176. Fluid flow communication between the respective rightand left-hand portions of the inner working chamber 82 are here provided by generally U-shaped passages or slots 178 and 180 which are formed to extend as shown through the core 156 into communication with the said working chamber portions.

In operation, and assuming counterclockwise rotation of the drive shaft 14 as indicated by the directional arrow in FIG. 13, it may be understood that fluid passage 168 will function as an inlet to the outer working chamber 84 while fluid passage 166 will function as an outlet therefrom, while fluid passage 178 will function as an inlet to the inner working chamber 82 and fluid passage 180 will function as an outlet therefrom. A particular advantage of the fluid machine form 13 resides in the fact that the particular shapes chosen for the housing aperture 152 and the core 156 will provide for respectively greater volumes of the inner and outer working chamber 82 and 84 whereby it may be understood that the displacement of the fluid machine may be substantially increased. In addition, it may readily be seen that each of the fluid passages I68, 178, I80 and 166 extend directly out of the fluid device whereby fluid may be flowed therefrom directly to appropriately connected inlet and outlet conduits without requiring changes in fluid flow direction to thus minimize frictional flow losses. Further, since the respective passages 178 and 180 are disposed between the spaced band extremities, it is made possible to markedly increase the area of these flow passages to thus even further reduce fluid frictional flow losses with resultant further increase in the overall efi'iciency of the provided fluid machines. As made clear by FIG. 14, front and back plates 182 and 184 would, of course, be provided to surround the respective housing 150 and core 156 to provide for the requisite formation of the fluidtight inner and outer working chambers.

The fluid machine form of FIG. is of markedly similar construction to that of FIGS. 13 and 14, whereby like components are identified by like reference numerals. In the embodiment of FIG. 15, however, it may readily be seen that the respective flexible band portions adjacent the respective flexible band extremities are curved to an even greater degree around the adjacent core surfaces to thus provide for greater volume of the respective inner and outer working chambers 82 and 84 with attendant greater increase in the displacement of the thusly provided fluid machines. Somewhat increased operational stresses will, of course, be placed upon the flexible band 70 by such increase in the requisite curvature of portions thereof, and it may be understood that the extent to which such curvature can be increased in an effort to increase fluid machine displacement and efficiency will, of course, be determined at least in part by the structural characteristics of the material utilized in the manufacture of the flexible band 70 as discussed in greater detail hereinbelow.

The fluid machine construction of FIGS. 16 through 19 is illustrative of a form wherein the respective band extremities are attached in contiguous manner while the respective housing aperture and core configurations are modified somewhat to provide for greater fluid machine displacement. More specifically, in this construction a flexible band mounting slot 312 is provided to extend upwardly as shown into core 46, while the housing 8 includes a very sharp, upwardly extending portion 314 extending into the said slot 312 with sufficient clearance provided therebetween for the insertion of the respective band extremities herein as shown. Preferably, although not necessarily, the respective extremities of the flexible band 70 are here bonded together prior to the insertion thereof in the band mounting slot 312. This construction provides for increased fluid machine displacement by increasing the effective volumes of the respective inner and outer working chambers 82 and 84 as described hereinabove with regard to the construction of FIG. 15 and, in addition provides for the added advantage of simplicity of band extremity attachment as should be obvious.

For purposes of making clear that despite these somewhat extreme changes in the respective configurations of the housing aperture 36 and the core 46, the operation of the fluid machine of FIGS. 16 through 19 is substantially the same as that described hereinabove with regard to the operation of the fluid machine of FIGS. 11A through 11D, it may be noted that with the drive pin 68 in the substantially top dead center position thereof as illustrated in FIG. 16, each of the core slots 47 and 4B is closed by the flexible band 70 and each of the housing slots 38 and 40 is opened thereby in the same manner as illustrated in FIG. 11C; that with the drive pin 68 in the lefthand position thereof intennediate the top and bottom dead center positions thereof as illustrated in FIG. 17, the housing slot 40 and the core slot 47 are closed by the flexible band 70 and the core slot 48 and housing slot 38 are opened thereby in the same manner described hereinabove with reference to FIG. 11D; that with the drive pin 68 in the bottom dead center positions thereof as illustrated in FIG. 18, the respective hous' ing slots 38 and 40 are closed and the respective core slots 47 and 48 are open in the manner described hereinabove and with reference to FIG. 11A; and that with the drive pin 68 in the right-hand position thereof intermediate the respective top and bottom dead center position thereof as illustrated in FIG. 19, the respective housing slot 38 and core slot 48 are closed by the flexible band 70 and the respective core slot 47 and housing slot 40- opened thereby in the manner described 12 hereinabove with regard to FIG. 113. Accordingly, it is believed made clear that the operation of the fluid machine of FIGS. 16 through 19 will be substantially the same as that described in detail hereinabove with regard to FIGS. 11A through 11D.

It is believed of interest to note that the adoption of the respective housing aperture and core configurations as illustrated in FIGS. 16 through 19 can be utilized to provide for approximately a fourfold increase in fluid machine displacement as compared, for example, to a fluid machine embodying the respective housing aperture and core configurations as illustrated in FIG. 6, and that it has been determined that this very significant increase in fluid machine displacement can be provided for without significant increase in the operational stresses applied to the flexible band 70 during fluid machine operation. One principal factor in enabling this very significant increase in fluid machine displacement resides in the fact that the throw or radius of the crank pin rotation of the fluid machine can be made two to three times greater through the form of the respective housing aperture and core configurations of the form of FIGS. 16 through 19 than it can be made through the form of FIG. 6 without deleterious effect upon the requisite flexural action of the flexible band.

With all forms of the fluid machine of the invention disclosed hereinabove, it may be understood that the displacement ratio between the outer working chamber 84 and the inner working chamber 82 will be approximately lzl for any combination of housing aperture, core and flexible band conflgurations and that this basic 1:] displacement ratio limitation is dictated by the generally circular path described by the movement of the band drive pin or drive bushing as the case may be. No problem is presented by this basic l:l displacement ratio limitationin fact the same may be readily understood to be a prerequisite for multistage pump applications-except for applications of the fluid machine of the invention as a two-stage compressor wherein it is, of course, required that the outer working chamber have a substantially larger displacement than the inner working chamber, assuming that the former is to operate as the first stage as is preferable for reasons discussed in detail hereinbelow.

FIG. 20 illustrates a construction wherein the displacement ratio between the outer and inner working chamber may range from approximately 3:! to 0.5:1 whereby it may be understood that the same would be suitable for use as a two-stage compressor. More specifically, and as seen in FIG. 20 wherein the housing is indicated at 500, the housing aperture at 502, the core at 504, and the flexible band at 506, the drive shaft and drive pin or drive bushing arrangement, formerly utilized to drive or take power from the flexible band, is replaced herein be a lever 508 which is slidably disposed in a slot provided therefor in a pivot pin 510 and is pivotally moveable therefrom within generally wedge-shaped slots 512 and 514 provided therefor in the core 504. Of course, the pivot pin 5 10 is disposed in fluidtight manner within the core to prevent fluid flow from wedge-shaped slot 512 to wedge-shaped slot 514.

The flexible band 506 is attached to the lever 508 adjacent one extremity thereof by the passage thereof through a slot in an attachment pin 516 which is, of course, mounted with freedom for rotation in the said lever. A peripheral cutout 518 is provided in the lower portion of the housing 500 and conventional crank shaft means as indicated generally at 520 are adjustably positioned therewithin and connection to the lower extremity of the lever 508 to drive the former in a generally circular path, with the result that the drive pin 516 will be driven in the opposite direction to describe a generally elliptical path as indicated by the dashed line 522.

Thus, as illustrated schematically in FIG. 21 with the lever 508 positioned within the slot in pivot pin 510 so that approximately three-fourths of the effective length of the lever is above the pin, and with the lower extremity of the lever 508 driven in a generally circular path as indicated at 524 by the appropriately positioned crank shaft 520, the drive it 516 will be driven in the generally elliptical path 522 with the result that the displacement of the outer working chamber 84, as represented by the area in FIG. 20 between the dotted line 526 and the face of the housing aperture 502, will be approximately three times as large as the displacement of the inner working chamber 82, as represented by the area in FIG. 20 between the band 506 in the shown position and the periphery of the core 504. This is believed made clear whereby, with the utilization of the housing slot 528 as the fluid machine inlet slot, the connection of the housing slot 530 to the core slot 532 to effect staging, and the utilization of the core slot 534 as the fluid machine outlet slot, the fluid machine of FIGS. 20 and 21 would be eminently satisfactory for use as a two-stage compressor.

FIG. 22 makes clear that the lever 508 can be adjusted in the pivot pin 510, with attendant adjustment of the disposition of the crank shaft 520 in the housing cutout 518, to provide for an approximately l:l working chamber displacement whereby the fluid machine of FIG. 20 could be utilized, for example, as a two-stage pump; while FIG. 23 illustrates adjustment of the lever 508 and crank shaft 520 to provide for an approximately 0.521 working chamber displacement ratio for utilization of the fluid machine of FIG. 20 as a double-acting, single-stage proportioning or metering device. Further, since a range of working chamber displacement ratios is provided for by the fluid machine construction of FIG. 20 it may be understood whereby the same would be very satisfactory for use as a metering or proportioning device wherein any of the available working chamber displacement ratios could be conveniently selected.

An alternate form of attachment means for drivingly attaching the flexible band to the fluid machine drive shaft is illustrated in FIGS. 24 and 25 and as best seen in the latter, the drive shaft 14 would, in this instance, terminate in a single throw crankshaft assembly which is constituted by a first crank throw which may serve as a bearing 216 journaled as illustrated in the backplate 10, a second crank throw which may serve as a bearing 218 journaled as illustrated in the front plate 6, and a crank or drive pin 220 connecting the same. In this construction, a bushing 222 is rotatably disposed around the crank or drive pin 220 so as to freely rotate relative thereto upon rotation of the drive shaft 14. In addition, bearings may, of course, be provided in the respective plates 6 and for the drive shaft 14.

For attachment of the flexible band 70 to this form of drive shaft arrangement, the former is cut out as indicated at 224 to the periphery of the drive bushing 222, and complementally shaped, generally semicircular band attachment flanges 230 and 232 formed at corresponding extremities thereof are disposed as shown around the resultant flexible band drive bushing assembly, whereupon attachment means in the nature of spaced rivets 234 are passed as shown through apertures provided therefor in the said attachment flanges and flexible band and secured in obvious manner in the said apertures to complete the attachment of the flexible band 70 to the drive bushing 222. Accordingly, it is believed made clear that upon driven rotation of the drive shaft 14, the crank or drive pin 220 and the drive bushing 222 will be driven to describe a circular path about the center of the drive shaft 14 with the said drive bushing rotating to the necessary extent about the said crank or drive pin 220 to effect the requisite flexible band flexural movement as described hereinabove with reference to FIGS. 11A through 11D and thereby provide for fluid machine operation as described in detail hereinabove with regard to the said Figures. Alternatively, it may be readily understood that driven flexural movement of the flexible band 70 by fluid under pressure in a fluid motor application will, of course, result in driven rotation of drive shaft 14 through the drive pin 220. A particular advantage of this method of flexible band-flexible band drive means attachment would reside in the fact that the stresses on the former would be somewhat relieved by being spread over a somewhat wider area of the extremities 230 and 232, as should be obvious.

FIG. 26 illustrates a generally similar form of flexible bandflexible band drive means attachment wherein a single, generally semicircular attachment member 236 is provided, and is fixedly secured to the upper portion of the drive bushing 222 by spaced attachment means in the nature of spaced rivets 238 to firmly press the adjacent portion of the flexible band 70 between the said drive bushing and attachment member 236 in the manner illustrated. As discussed directly hereinabove with regard to the flexible band drive means attachment form of FIGS. 24 and 25, the attachment means illustrated by FIG. 26 would again provide the advantage of maximizing the area of contact between the flexible band and the flexible band drive means to thereby minimize the stresses imposed upon the latter during fluid machine operation.

A flexible band 70 of somewhat different contour, and a somewhat different method of band extremity attachment which enables the convenient adjustment of the eflective length of the said band, are illustrated by the construction of FIGS. 27 and 28. More specifically, as seen therein the aperture 36 in the housing 8, and the core 46, are again of generally complemental shape but each terminate at the respective lower extremities thereof in a generally wedgeshaped configuration. In this construction, a flexible band mounting slot 300 is provided to extend as shown from the lower extremity of the housing aperture 36 completely through the housing 8 to the lower extremity thereof, and a readily removable plate 302 is provided to seal the said flexible band mounting slot 300 and maintain the requisite fluidtightness of the respective inner and outer working chambers 82 and 84 as should be obvious.

As seen in FIG. 28, the flexible band 70 utilized in this construction also terminates in a substantially wedge-shaped lower extremity and it is believed clear that the affixation of the respective band extremities may readily be efl'ected by the insertion thereof into the flexible band mounting slot 300 in the housing 8. A particular advantage of this construction resides in the fact that the same provides for the ready and convenient adjustment of the effective length of the flexible band 70. More specifically, it may be readily understood that such adjustment may be conveniently effected through the simple removal of the plate 302 and the manipulation of the respective band extremities further into or out of the flexible band mounting slot 300.

This provision for convenient adjustability of the effective length of the flexible band 70 enables the adjustment thereof to compensate for production tolerances, and further, enables the convenient modification of the overall flexible band tension to thus enable the adjustment of the sealing force which will be exerted by the flexible band 70 in closing the respective fluid passages or slots 38, 40, 47 and 48. This is to say that if the effective length of the flexible band 70 is increased through movement of the respective band extremities in the flexible band mounting slot 300 upwardly as seen in FIG. 27, the sealing force exerted by the band enclosing the said slots will be increased, while shortening of the effective flexible band length by movement of the respective band extremities further downwardly in the said flexible band mounting slot will, of course, decrease the sealing force.

A means of providing for adjustment of the effective length of a generally heart-shaped flexible band during fluid machine operation is illustrated in FIG. 29, it being reiterated here that the provision for such flexible band effective length adjustment enables the compensation for manufacturing tolerances and the ready adjustment of the sealing force of the band against the respective housing and core slots.

In FIG. 29, the housing is indicated at 460, the housing aperture at 462, the core at 463, the respective housing and core slots at 464, 466, 468 and 470, and the flexible band at 472. The respective flexible band extremities are attached as shown by a rivet or rivets 474 to a flat bar 476 and the resultant band extremity bar assembly inserted as shown in a generally radially extending slot 478 provided therefor in the core 463. A leaf spring 480 is also disposed in the slot 478 and functions to press against the adjacent extremities of the flexible band 472 and bar 476 to bias the same radially outward of the slot 478, while an adjustment screw 482 extends as shown through a complementally threaded aperture provided therefor in the housing 460 into contact with the opposite extremity of the bar 476. Accordingly, it is believed made clear that the position of the bar 476 within the housing slot 478 and, as follows, the effective length of the flexible band 472, may be readily adjusted during operation of the fluid machine through the simple turning of the adjustment screw 482 as desired. A particular advantage of providing for adjustment of the effective length of the flexible band during fluid machine operation resides in the fact that relevant operational parameters of the latter may be measured and observed and brought to desired values or levels through the simple rotation of the adjustment screw 482.

In the fluid machine construction of FIGS. 30 through 32 the flexible band, here indicated generally at 304, comprises a first flexible band member 306 and a second flexible band member 308 each of which is preferable prestressed to assume the configuration thereof depicted in FIG. 32 prior to the installation thereof in the fluid machine. This installation is effective by the insertion of the respective upper extremities of the flexible band members 36 and 308 in a slot 78 provided therefrom in the drive pin 68, and by the insertion of the lower band member extremities in a flexible band mounting slot 310 provided therefor at the lower extremity of the housing aperture 36. In addition to the advantage of providing for ready adjustability of the effective length of the flexible band as discussed directly hereinabove with regard to FIGS. 27 and 28, it may be understood that the flexible band construction of FIGS. 30 through 32 provides the additional advantage of minimization of band stress at the point of attachment thereof to the drive pin, to wit, the band mounting slot 78, and easier fabrication of the respective flexible band members 306 and 308 which may, of course, by simply produced as straight band members, as illustrated in FIG, 31, and then prestressed to assume the configurations thereof as illustrated in FIG. 32.

A somewhat different method of flexible band construction and flexible band extremity attachment is illustrated by FIGS. 33 through 35. More specifically, and as best seen in FIG. 35, although the respective housing, housing aperture and core configurations may readily be seen to be substantially similar to those described hereinabove with regard, for example, to FIG. 6, the flexible band here indicated generally at 320 is in this instance of two-piece construction in comprising a flexible band member 322 and a flexible band member 324. As seen in FIGS. 33 and 34, the respective lower extremities of the flexible band members 322 and 324 are attached between the housing 8 and core 46 through the use of attachment pins 326 and 328 which are inserted as shown in apertures complementally by the said housing and core. Affixation of the respective band extremities to these attachment pins is effected in each instance by the simple turning of the band extremity there around within the said apertures as clearly illustrated in FIG. 34 to thus provide for some freedom of rotation of the band extremities relative to the said attachment pin with attendant decrease in operation band stress.

Attachment of the respective upper band member upper extremities to the drive pin 68 is provided for by the freely rotatable disposition of a flexible band attachment bushing 330, including attachment flanges 332 and 334, around the drive pin 68, and the attachment of the upper extremity of flexible band member 324 between the said attachment flanges through the passage of a plurality of fastening means in the nature of rivets 336 therethrough, in the manner best illustrated in FIGS. 35 and 36. Generally semicircular band attachment members 338 and 340 are rotatably disposed asshown around the band attachment bushing 330, and the said band attachment members may be seen to respectively comprise attachment flanges 342 and 344, whereupon it may be readily understood that-the passage of the upper extremity of the flexible band member 322 to the drive pin 68. By this construction it is believed made clear that the respective flexible band members 322 and 324 which form the flexible band 320 will be free to rotate or pivot at each point of attachment thereof whereby the operational stresses imposed upon the flexible band 320 during fluid device operation will be substantially reduced. As a result it is believed clear that the respective flexible band members 322 and 324 which form the flexible band 320 can be made of much thicker and stronger material that if the same were rigidly attached at the respective attachment points thereof to the drive pin and housing and core connections to thus enable higher pressure applications of the fluid machine of the invention due to the greater flexible band strength provided by the increased thickness thereof.

FIG. 37 illustrates the utilization of a flexible band 320 constructed and attached in the manner described in detail directly hereinabove with regard to FIGS. 33 through 36, in a fluid machine which comprises housing aperture and core configurations of the general nature described in detail hereinabove with regard to FIGS. 16 through 19, while FIG. 38 illustrates the utilization of a flexible band 320 in a fluid device comprising a housing aperture and core configured in the manner described in detail'hereinabove with regard to FIG. 15, whereby it is believed made clear that the two-piece band construction embodied by the flexible band 320 of FIG. 33 is equally applicable to utilization in fluid devices comprising differently configured housing apertures and cores. This is to say, for example, that the construction of FIG. 37 may be understood to combine the significant advantages of reduced operational flexible band stresses provided for by the use of flexible band 320 and the substantially increased fluid device displacement provided for through the utilization of a housing aperture and core configured as illustrated; while FIG. 38, in addition to providing the combined advantages of the construction of FIG. 37, may be understood to provide the additional advantage of enabling a substantial increase in the respective flow areas of the core passages or slots 178 and 180, as described in detail hereinabove with regard to FIG. 15.

As discussed hereinabove, the strength of the flexible band may be readily increased for higher pressure, fluid machine application, without decrease in the flexiblity thereof or increase in the operational stresses applied thereto, by fonning the band of a laminated or multilayer construction. Thus, as seen in FIG. 39 for a generally circularly configured flexible band as indicated at 440, the same may comprise respective band members 442, 444 and 446 disposed as shown in surface contact and attached to a flexible band drive bushing 448 by band attachment member 450 and rivets 452 to form a threeply flexible band of substantially increased strength as should be obvious. The respective extremities of the band 440 may be bent, for example, as indicated at 454 for disposition in a band mounting slot as discussed hereinabove, and the said band extremities may be bonded together if desired.

FIG. 40 illustrates a substantially identical, multilayer band construction wherein the same is generally heart-shaped, and like reference numerals are applied to like band components. FIG. 40 additionally illustrates that an attachment rivet 456 may be extended through the respective band member extremities for obvious purpose. It may be understood that the method of attachment of multilayer bands can be basically the same as for single bands described above and shown in FIGS. 8, 24, 29, 30, 33, 35 as examples.

FIG. 41 makes clear that, in each instance, the respective band members 440, 442 and 444 are disposed in substantial surface contact; while FIG. 42 illustrates that the three-ply flexible band 440 may alternatively be attached to the drive pin 68 assuming the pin to be rotatable in the shaft, by the passage of the former through a band attachment slot 78 in the latter and the subsequent passage of a rivet 458 therethrough.

It has been determined that whether the multilayer flexible band 440 is generally circularly shaped as in FIG. 39, or generally heart-shaped as in FIG. 40, the deflections of the band 440 attendant fluid machine operation will not function to effect band member separation. This is believed clearly illustrated by FIG. 43 wherein may readily be seen that no band member separation has occurred during deflection, as would occur during fluid machine operation, of the multilayer band 440 from a generally circular configuration as indicated at 440' to a generally oval configuration as indicated at 440. This is ensured by the fact that respective changes in length of the respective parts of the band members in essence cancel out as is believed made clear by the subject Figure.

Some sliding movement may, however, occur between the respective contacting surfaces of the band the respective 442, 444 and 446, and it may be understood that the frictional losses attendant such sliding movement may be readily minimized by the application of a suitable lubricant of permanent fonn, as for example, a graphite or molybdenum compound, to the respective contacting surfaces of the band members.

FIGS. 44 through 48 illustrate a modified form of construction of the flexible band which provides for improved sealing of the respective edges thereof relative to the respective inner end faces of the front and backplates. More specifically, by this construction is provided a flexible band which is constituted by three distinct flexible band members, to wit, an outer band member 200 and inner band members 202 and 204, operatively disposed in the manner made clear by FIG. 48. As illustrated, the outer band member 200 is of a width which is somewhat less than the spacing between the respective front and backplate end faces, while the combined widths of the inner band members 202 and 204 is just slightly less than the extent of the said space.

For purposes of maintaining the respective outer edges 206 and 208 of the inner flexible band members 202 and 204 in substantially firm surface contact with the respective front and backplate end faces 201 and 203, spaced tabs 210 are cut and bent outwardly as illustrated from the inner edge 212 of the inner flexible band member 202 whereby, when the band members are assembled in the manner clearly depicted in FIG. 48, these tabs will function to press against the adjacent inner edge 214 of the inner flexible band member 204 with the result that the respective outer band member edges 206 and 208 will be pressed into reasonable firm surface contact with the respective front and backplate end faces 20] and 203 to thereby maintain substantially fluidtight seals therebetween and prevent fluid leakage around the combined band assembly between the fluid machine inner working chamber 82 and outer working chamber 84 with resultant inhibition of any decrease in fluid machine efl'rciency from such leakage. Although, the amount of clearance, if any, provided between the flexible band member outer edges 206 and 208 and the respective front and backplate end surfaces 201 and 203, and the amount of sealing pressure to be provided for by the spaced tabs 210, will vary with fluid machine application, it may be noted that for a typical application of the fluid machine of the invention in the pumping of liquids, it has been determined that the allowance of a clearance of approximately l/ I000 of an inch between the said flexible band member edges and front and backplate end faces, and the provision of a sealing pressure ranging from approximately one-half to l pound, has proven particularly satisfactory.

A somewhat modified form of flexible band construction which again includes the built-in provision for the maintenance of a predetermined band edge from and backplate end face sealing pressure is illustrated in FIG. 49 and may be readily seen to be identical to the construction described directly hereinabove with regard to FIGS. 44 through 48, with the exception that in the flexible band construction of FIG. 49, an additional flexible band member 213 is added to the side of the flexible band members 202 and 204 remote from the outer band member 200. The band member 213 is of substantially the same width as the latter although, of course, of slightly lesser circumferential extent, and is maintained as shown in firm surface contact with the respective inner surfaces of the bands 202 and 204 to thereby provide for increased structural rigidity of the flexible band construction. Preferably, if either of the flexible band constructions of FIG. 48 or FIG. 49 is utilized, the same would as an example be attached to the drive pin 68 through use of a band attachment slot 78 formed in the latter as illustrated in FIG. 42, and further, in such instances, each of the flexible band members which make up the flexible band construction would be continuous, as clearly illustrated in FIG. 44 for the band construction of FIG. 48.

Referring now to the construction of FIGS. 50 and 52, the housing is indicated at 350 and comprises an aperture 352, while the core is indicated at 354. Slots 356 and 358 are provided in the core 354, and slots 360 and 362 are provided in the housing 350. The flexible band is indicated generally at 364 and comprises an outer band member 366 and an inner band member 368 spaced as shown to provide a passage 370 therebetween for the flow of an externally introduced, flexible band cooling fluid therethrough. To this effect, a band attachment pin 372 which extends, as best seen in FIGS. 50 and 53 without the fluid machine, is provided and includes a cooling fluid inlet passage 374 and a cooling fluid outlet passage 376 extending respectively therethrough into fluid flow communication with the internal band passage 370.

The respective lower extremities of the flexible band members 366 and 368 are affixed to the band attachment pin 372 by the overlapping thereof around the respective upper and lower portions of the latter and the passage of spaced, band attachment means in the nature of rivets 378 therethrough in the manner best seen in FIG. 51.

In this construction the drive pin is again indicated at 68 and a band drive bushing as generally indicated at 382 is rotatably disposed thereover. The band drive bushing 382 is of the stepped configuration made clear by FIG. 52 and comprises end flanges 384 and 386 spaced as shown by the main or body portion 388 of the said bushing.

For attachment of the respective outer and inner band members 366 and 368 to the band drive bushing 382, the same are respectively passed around the upper and lower peripheral portions of the band drive bushing flanges 384 and 386 and maintained in firm surface contact therewith by flexible band attachment members 390 and 392 which overlie the said band members, and by spaced attachment means in the nature of rivets 394 which extend as shown through the respective band attachment members, inner and outer band members and band drive bushing to complete and maintain the band member drive pin attachment assembly. The pin 68 being fixed to the drive shaft 14, is able to rotate freely within the bushing 382. By this construction it may be understood that spaces, as indicated at 396 and 398 in FIGS. 47 and 48, will be provided between the respective inner surfaces of the band members 366 and 368 and the body portion 388 of the bushing 382, and that these spaces will function to enable the flow of band cooling fluid through the band member drive pin attachment assembly to complete the formation of the cooling fluid passage 370.

FOr example, in operation it may readily be understood that, concomitantly with driven rotation of the drive shaft 14 and resultant flexural movement of the flexible band 364 as described hereinabove, cooling fluid under suitable pressure will be admitted through inlet passage 374 in band attachment pin 372 to flow therefrom between the inner and outer band members 368 and 366 through passage 370 formed therebetween and through spaces 396 and 398 for subsequent exhaust from the fluid machine through outlet passage 376 in band attachment pin 372.

The construction of FIG. 54 illustrates the incorporation of flexible band cooling means in a fluid machine wherein the flexible band is discontinuous. More specifically, this embodiment, the housing is indicated at 400, the housing aperture at 402, the core at 404, and the respective housing and core slots of flow passages at 406, 408, 410 and 412. The cooled discontinuous flexible band assembly is indicated generally at 414 and comprises an inner band member 416 and an outer band 

2. In a fluid machine as in claim 1 wherein, said one working chamber is formed between one face of said flexible band means and said core means.
 3. In a fluid machine as in claim 2 wherein, a second generally annular working chamber is formed between the opposite face of said flexible band means and the face of said chamber and said fluid machine comprises second, spaced inlet and outlet means communicating with different portions of said second working chamber whereby, said flexural movement of said flexible band means will be concomitantly effective to alternately expand and contract said different portions of said second working chamber and alternately open and close said second inlet and outlet means whereby, the movement of fluid between said second inlet and outlet means may be concomitantly effected.
 4. In a fluid machine as in claim 2 wherein, said inlet and outlet means extend at least in part through said core means.
 5. In a fluid machine as in claim 3 wherein, said inlet and outlet means extend at least in part through said core means.
 6. In a fluid machine as in claim 3 wherein, said second inlet and outlet means extend at least in part through said casing.
 7. In a fluid machine as in claim 1 wherein, said drive means are adapted to move at least said second portion of said flexible band means in a generally circular path.
 8. In a fluid machine as in claim 2 wherein, said drive means are adapted to move at least said second portion of said flexible band means in a generally circular path.
 9. In a fluid machine as in claim 3 wherein, said drive means are adapted to move at least said second portion of said flexible band means in a generally circular path.
 10. In a fluid machine as in claim 7, wherein said holding means comprises means affixing respective extremities of said flexible band means, and said drive means are connected to said flexible band means generally intermediate said respective affixed extremities thereof.
 11. In a fluid machine as in claim 8, wherein said holding means comprises means affixing respective extremities of said flexible band means to said casing, and said drive means are connected to said flexible band means generally intermediate said respective affixed extremities thereof.
 12. In a fluid machine as in claim 9, wherein said holding means comprises means affixing respective extremities of said flexible band means to said casing, and said drive means are connected to said flexible band means generally intermediate said respective affixed extremities thereof.
 13. In a fluid machine as in claim 12 wherein, said casing comprises housing means through which said chamber extends, and said respective flexible band means extremities are affixed to said casing intermediate said housing and core means.
 14. In a fluid machine as in claim 10 wherein, said respective band means extremities are affixed to said casing with freedom for rotation therebetween.
 15. In a fluid machine as in claim 12 wherein, said respective band means extremities are affixed to said casing with freedom for rotation therebetween.
 16. In a fluid machine as in claim 7 wherein, said drive means connected to said flexible band means to flexurally move the same are connected thereto with freedom for rotation therebetween.
 17. In a fluid machine as in claim 15 wherein, said drive means connected to said flexible band means to flexurally move the same are connected thereto with freedom for rotation therebetween.
 18. In a fluid machine as in claim 10, wherein said flexible band means comprise a first band member extending from one affixed extremity thereof to the opposite extremity thereof which opposite extremity is connected to said drIve means; and a second band member which extends from an affixed extremity thereof to the opposite extremity thereof which opposite extremity is also connected to said drive means.
 19. In a fluid machine as in claim 12 wherein, said flexible band means comprise a first band member extending from one affixed extremity thereof to the opposite extremity thereof which opposite extremity is connected to said drive means; and a second band member which extends from an affixed extremity thereof to the opposite extremity thereof which opposite extremity is also connected to said drive means.
 20. In a fluid machine as in claim 13, wherein, said respective flexible band extremities are affixed together to form continuous band with the point of band extremity affixation lying generally intermediate said respective inlet and outlet means.
 21. In a fluid machine as in claim 18 wherein, said respective flexible band extremities are affixed together to form a continuous band with the point of band extremity affixation lying intermediate said respective inlet and outlet means.
 22. In a fluid machine as in claim 12 wherein, said respective band extremities are affixed to said casing at spaced points to form a discontinuous band, and wherein at least one of said inlet means and one of said outlet means extend into communication with said working chamber intermediate said respective band extremities.
 23. In a fluid machine as in claim 9 wherein, said flexible band means comprise first and second substantially coextensive flexible band members disposed in edge-to-edge relationship and wherein said first flexible band member comprises spaced tab means extending from an edge thereof into contact with the adjacent edge of said second flexible band member to create a biasing force to seal the opposite edges of said band members against said casing.
 24. In a fluid machine as in claim 20 wherein, said flexible band means comprise first and second, generally coextensive flexible band members, and said drive means and said holding means each comprise means to space said first and second flexible band members to form a space therebetween which is continuous and generally coextensive with said band members, and further comprising means cooperatively associated with said coextensive flexible band members for the introduction of a cooling fluid to said space to cool said flexible band means during operation of the fluid machine.
 25. In a fluid machine as in claim 22 wherein, said flexible band means comprise first and second, generally coextensive flexible band members, and said drive means and said holding means each comprise means to space said first and second flexible band members to form a space therebetween which is continuous and generally coextensive with said band members, and further comprising means cooperative associated with said coextensive flexible band members for the introduction of a cooling fluid to said space to cool said flexible band means during operation of the fluid machine.
 26. In a fluid machine as in claim 12 wherein, said flexible band means comprise a plurality of generally coextensive flexible band members which are disposed in surface contact to form a laminate.
 27. In a fluid machine as in claim 20 further comprising, means cooperatively associated with said respective flexible band means extremities and operable to vary the effective length of said flexible band means within said first and second working chambers.
 28. In a fluid machine as in claim 3 wherein, said drive means are operative to move at least said said second portion of said flexible band means in a generally elliptical path.
 29. In a fluid machine as in claim 28 wherein, said flexible band connected means comprise lever means which are pivotally mounted within said core with one extremity thereof extending into said chamber and connected to said flexible band means therewithin, and means connected to the other extremity of said lever to drive the same in a generally circuLar path.
 30. In a fluid machine as in claim 28, wherein said holding means affix respective extremities of said flexible band means to said casing, and wherein said drive means connected to said flexible band means to flexurally move the same are connected thereto intermediate said respective affixed extremities thereof.
 31. In a fluid machine as in claim 1 further comprising, check-valved conduit means in communication with said outlet means and operative to permit fluid flow only from the latter to the former.
 32. In a fluid machine as in claim 3 further comprising, check-valved conduit means in communication with said outlet means and operative to permit fluid flow only from the latter to the former.
 33. In a fluid machine as in claim 5, further comprising, check-valved conduit means in communication with said outlet means and operative to permit fluid flow only from the latter to the former.
 34. In a fluid machine as in claim 7 wherein, said drive means to flexurally move said flexible band further comprise means to introduce fluid under pressure to said working chamber through said inlet means.
 35. In a fluid machine as in claim 8 wherein, said drive means to flexurally move said flexible band further comprise means to introduce fluid under pressure to said working chamber through said inlet means.
 36. In a fluid machine as in claim 9 wherein, said drive means to flexurally move said flexible band means further comprise means to introduce fluid under pressure to at least one of said working chambers through at least one of said inlet means.
 37. A fluid machine comprising a casing having first and second, substantially fluidtight spaces formed therein, generally arcuate core means fixedly disposed within each of said spaces and spaced at least in part from said casing to respectively form generally annular chambers therebetween, flexible band means disposed in each of said chambers to surround each of said cores at least in part and form at least one generally annular working chamber in each of said chambers, spaced fluid inlet and outlet means communicating with different portions of each of said working chambers, and means for flexurally moving each of said flexible band means to alternately expand and contract different portions of said working chambers and concomitantly alternately open and close said spaced fluid inlet and outlet means whereby, the movement of fluid between said inlet and outlet means may be effected.
 38. In a fluid machine as in claim 37 wherein, each of said one generally annular working chambers is formed between one face of said flexible band means and said core means, and said inlet and outlet means extend respectively through each of said core means into communication therewith.
 39. In a fluid machine as in claim 38 wherein, a second generally annular working chamber is formed in each of said chambers between the respective opposite faces of said flexible band means and said chamber, and said fluid machine further comprises spaced inlet and outlet means extending respectively through a part of said casing into communication with different portions of each of said second working chambers whereby, said flexural movement of said flexible band means will be concomitantly effective to alternately expand and contract said different portions of said second working chambers and alternately open and close said inlet and outlet means which extend through said casing part whereby, the movement of fluid between the latter inlet and outlet means may be concomitantly effected.
 40. In a fluid machine as in claim 39 wherein, said generally annular chambers and said core means are disposed in generally back-to-back relationship within said casing.
 41. In a fluid machine as in claim 39 wherein, said generally annular chambers and said core means are disposed in arcuately displaced manner around the center of said casing within said casing.
 42. In a fluid machine as in claim 41 wherein, said means to flexurally move said flexible band means comprise means connected to each of said flexible band means and operative to move at least respective portions thereof in generally circular paths, and drive means generally centrally disposed relative to said casing and connected to each of said flexible band moving means.
 43. A fluid machine comprising a casing having a substantially fluidtight space formed therein, core means fixedly disposed within said space and spaced at least in part from said casing to form a generally annular chamber therebetween, flexible band means disposed in said chamber to surround said core means at least in part and form first and second generally annular working chambers therewithin, said first working chamber being formed between one face of said flexible band means and the face of said chamber, said second working chamber being formed between the other face of said flexible band means and the face of said core means, spaced fluid inlet and outlet means communicating, respectively, with different portions of said first and second working chambers, and means for flexurally moving said flexible band means to alternately expand and contract different portions of said working chambers and concomitantly alternately open and close said spaced fluid inlet and outlet means whereby the movement of fluid between said inlet and outlet means may be effected.
 44. In a fluid machine as in claim 43 wherein, said core means is fixedly disposed in said space.
 45. In a fluid machine as in claim 43 wherein, said inlet means communicate with corresponding portions of said first and second working chambers, and said outlet means communicate with corresponding portions of said first and second working chambers. 